The invention is directed to a cyclone separator, particularly for direct heat transmission from the hot exhaust gasses of a rotary tubular kiln/cyclone suspension type heat exchanger for cement clinker manufacture onto the raw cement meal, having tangential delivery of gas and raw meal, product discharge in the lower cyclone area and having an immersion pipe for gas elimination that is composed of a plurality of segments, which immersion pipe, projects centrally from above into the cyclone separator and is suspended at the cyclone ceiling, whereby the immersion pipe segments have their upper end releasably connected by screw bolts to the gas withdrawal conduit insulated by a refractory lining.
In systems for manufacturing cement clinker from raw cement meal, the raw meal is thermally treated by pre-heating, calcining, sintering and cooling, whereby the exhaust gas stream of the sintering unit and the exhaust air stream of the cooling unit from the clinker cooler are utilized, either separately or in common, for the calcination of the raw meal in a calcining unit supplied with fuel that is still located outside the sintering furnace. The preheating unit is usually composed of a plurality of suspension type heat exchanger cyclones arranged above one another through which the raw cement meal successively migrates in a combined co-current, counter-current stream relative to the hot exhaust gas of the calcining unit or, respectively, of the rotary tubular kiln. The product material pre-calcined in the calcining unit is thereby separated from the hot gas in the lowest cyclone of the cyclone suspension type heat exchanger system and is introduced into the rotary tubular kiln. It is self-evident that the hot gas cyclones of the cyclone suspension type heat exchanger line, particularly the lowest cyclone that comes into contact with hot gas and hot meal having a temperature of, for example, 700 through 950.degree. C., are exposed to a high mechanical, chemical and thermal stressing and, thus, to high thermo-chemical and abrasive wear. This is especially true of the immersion pipe centrally projecting from above into the cyclone separator.
Given a cyclone separator exposed to these high stresses, it is therefore already known (DE-C-32 28 902) to compose the immersion pipe of a plurality of segments and to suspend the immersion pipe segments at the cyclone ceiling with a hook-shaped fashioning or to releasably connect the immersion pipe-segments with radially arranged screw bolts to the gas discharge conduit of the cyclone that is insulated by a refractory lining, in order to avoid deformations at the immersion pipe cladding even given high, thermal alternating stresses, and in order to be able to replace individual immersion pipe segments with comparatively little time and work expenditure, in case of wear. However, the screwed connections of the immersion pipe segments were thereby not protected against the thermo-chemical stresses, with the consequence that the risk was not precluded that the screwed connection unscrewed after a certain time, after which, given the lack of further safety measures, the appertaining immersion pipe segment could drop down into the cyclone separator.